Extent and symmetry of post-juvenile moult as predictors of future performance in Greenfinch Carduelis chloris

Abstract

The extent of post-juvenile moult in passerines is highly variable, but the causes and consequences of such variability remain poorly understood. We tested the hypothesis that the extent and symmetry of post-juvenile moult of Greenfinches Carduelis chloris may be used as reliable predictors of their winter/spring body condition. We found a quadratic relationship between moult extent and the body mass/wing length ratio during the winter/spring period. We also found that Greenfinches with higher degree of moult symmetry had greater winter/spring fat reserves. Our results suggest that the extent and symmetry of post-juvenile moult may be considered as adaptive traits with certain fitness consequences. © 2012 The Author(s).